In comparison to wired telecommunication networks, wireless communication networks are likely to be affected by transmission errors since wireless communication networks are comparatively sensitive to multipath fading and Doppler shift (which occurs due to a difference in the relative velocity between a transmitter and a receiver) among other factors. Several factors are considered for determining the transmission efficiency of a communication channel, be it a wired communication channel or a wireless communication channel. Most common amongst those factors are Signal to Noise Ratio (SNR) and bit rate (bit rate specifies the number of bits which are erroneously transmitted out of a particular number of transmitted bits). It is a well established fact that the values of SNR and bit rate are far greater for a wireless communication channel than that of a wired communication channel.
Referring to FIG. 1, there is shown a conventional communication network 100 comprising two mobile stations (MS), a first mobile station 10 and a second mobile station 12. Two network elements, preferably eNodeBs, namely a first eNodeB 14 and a second eNodeB 16 interface with respective mobile stations via corresponding wireless communication channels. Simultaneously, the two eNodeBs 14 and 16 interface with other network elements (including but not restricted to routers, switches) via corresponding wired communication channels. A typical data transfer operation from the first mobile station 10 to the second mobile station 12 requires the data packets to be transmitted from the first mobile station 10 to the first eNodeB 14 via a wireless communication channel. Subsequently, the first eNodeB 14 transmits the data packets over a wired communication channel to the second eNodeB 16 which in turn transmits the data packets to the second mobile station 12 via a wireless communication channel.
When data is transmitted over the communication network from the first mobile station 10 to the second mobile station 12, due to congestion therein (congestion is typically prevalent at fixed network elements such as routers and switches), some of the data packets (transmitting the data) are typically dropped. Given the fact that the data packets are transmitted in adherence to the Transmission Control Protocol (TCP) which is an end-to-end congestion protocol, the TCP entity of the first mobile station 10 would have retransmit any dropped data packets. However, since the first mobile station 10 communicates with the first eNodeB 14 via a wireless communication channel, there could be substantial delay in retransmission of the dropped packets, due to the fact that wireless communication channels are time varying channels. Further, in an exemplary scenario, if a data packet under transmission is lost in the wired network connecting the first eNodeB 14 to the second eNodeB 16, the second mobile station 12 sends a NACK (negative acknowledgement) message to the first mobile station 10 indicating non-receipt of the transmitted data packet. In such a case, the first mobile station 10 would have to retransmit the dropped lost data packet using the wireless communication channel that connects the first mobile station 10 and the first eNodeB 14. Since the data packet has been lost/dropped due to congestion in the wired network connecting the first eNodeB 14 to the second eNodeB 16, retransmitting the dropped data packet using the wireless channel connecting the first mobile station 10 and the first eNodeB 14 would result in unnecessary utilization of wireless communication channel thereby adversely affecting the availability of wireless communication channel for subsequent data transmission operations. Since wireless resources are scarce, there has been felt a need to better manage the available wireless resources (including wireless communication channels) by bring about a reduction in repetitive usage of wireless communication channels for the purpose of retransmitting dropped data packets.